Genetics Flashcards
What is Kleinfelter Syndrome?
47 XXY - male has an additional X
What are the clinical features of Kleinfelter Syndrome?
Tall, wider hips, weaker muscles, small testicles, shyness, reduced libido, gynaecomastia, infertility
What is high in Kleinfelter syndrome?
FSH and LH
What is the management of Kleinfelter Syndrome?
Testosterone injections
IVF
SLT
Physio
Educational support
What is Turners Syndrome?
A female has a single X making them 45 XO
What are the clinical features of Turners Syndrome?
Short stature, spoon shaped nails, webbed neck, high arch palate, downward sloping eyes, cubitus valgus, broadly spaced nipples
What is the treatment of Turner Syndrome?
Growth hormone therapy
Oestrogen and progesterone
Fertility treatment
What is Down Syndrome?
Three copies of chromosome 21
What are the clinical features of Downs?
Brachycephaly (small head and flat back)
Short neck and short stature
Flattened facial features
Prominent epicanthic folds
Upward sloping palpebral fissures
Single palmar crease
Wide sandal gap
What is the combined test for Downs?
USS at 11-14 weeks measures nuchal translucency - back of head thickness
Give 2 antenatal testing techniques for downs
Chorionic villus sampling
Amniocentesis
What is the gold standard test for Downs
karyotype analysis of foetal cells via chorionic villus sampling or amniocentesis
What is checked 2 yearly in Downs?
Thyroid
What is Edward Syndrome?
Trisomy 18
What are some USS findings of Edward Syndrome?
Growth restriction
Single umbilical artery
Small placenta
Polyhydraminos
Strawberry shaped head
What are some features of Edward Syndrome in live born infants?
Congenital heart defects
Severe GORD
Severe intellectual disability
Seizures
What is Patau Syndrome?
Trisomy 13
What are some prenatal presentations of Patau Syndrome?
cleft lip and palate
Microcephaly
Cutis aplasia - skin missing from scalp
Kidney cysts
Small penis
Microphthalmia - small eyes
Rocket bottom feet
What are some postnatal features of Patau Syndrome?
Low birth weight
Sloping forehead
Close set eyes
Short nose
Cleft palate
Small jaw
Low set ears
Cataracts
Seizures
What is fragile X syndrome?
Mutation in FMR1 gene on X chromosome important in cognitive development
Always males
What is the presentation of fragile X syndrome?
Delayed S&L
Intellectual disability
Long, narrow face and large ears
Large testicles
Hypermobile joints
What is muscular dystrophy?
Progressive weakness and loss of muscle mass due to mutations in genes responsible for production of dystrophin resulting in progressive muscle degeneration
What are the clinical features of muscular dystrophy?
Progressive weakness
Delayed milestones
Waddling gait
Faltering growth
Fatigue
Intellectual impairment
Tip toe walking
What is Gowers sign?
DMD - child climbs up their legs when rising from the floor
What is calf pseudohypertrophy?
accumulation of connective tissue and fat replacing muscle tissue
What are the investigations for muscular dystrophy?
Serum creatine kinase leaks from damaged muscle cells
Genetic analysis
Muscle biopsy - dystrophin protein
ECG and ECHO
What is Angelman Syndrome?
Loss of function of UBE3A gene (deletion on C15)
What are some clinical features of Angelman syndrome?
Happy demeanour
Wide mouth with widely spaced teeth
Fascination with water
Coordination and balance problems
Inappropriate laughter
Hand flapping
ADHD
What is Prader Willi Syndrome?
Loss of functional genes on proximal arm of C15 from father
What are some features of Prader Willi?
Constant insatiable hunger causing obesity
Poor muscle tone
Mild-moderate learning disability
Hypogonadism
Fairer soft skin
Dysmorphic features
Narrow forehead
Almond eyes
Squint
What are the clinical features of Noonan Syndrome?
Thickly hooded eyes
Wispy hair
Discoloured skin spots
Large, tall forehead
Widely spaced nipples and eyes
Webbed neck
What are some conditions associated with Noonans?
Congenital heart disease - PVD, ASD
Cryptochidism
Learning disability
Bleeding disorders
What is the diagnosis for Noonan?
Amniocentesis
Foetal USS
Chorionic villus sampling
Genetic testing
Physical exam at birth
What is William Syndrome?
Deletion of 25-28 genes on one copy of C7 usually due to random deletion
What are the clinical features of Williams Syndrome?
Broad forehead
Very sociable and trusting
Starburst eyes
Long philtrum
Flat nasal bridge
Small chin
What are some conditions associated with Williams Syndrome?
ADHD
Supravalvular aortic stenosis
Hypercalcaemia
Hypertension
